Brake disk for a motorcycle



FIG. 1 is a front view of the brake disk for a motorcycle showing our new design;

FIG. 2 is a back view thereof;

FIG. 3 is right side view thereof;

FIG. 4 is a top view thereof.

FIG. 5 is a bottom view thereof;

FIG. 6 is an enlarged sectional view taken along line 6—6 in FIG. 1; and,

FIG. 7 is a perspective view thereof.

A left side view thereof is a mirror image of the right side view. 

The ornamental design for a brake disk for a motorcycle, as shown and described. 